Automatic stop for start and stop motors



A 1931. c. H. BISSELL 1,817,172

AUTOMATIC STOP FOR'START AND STOP MOTORS Filed April 26, 1 28 Q x y r k/4- 9r IIYVENTOR. /V

awn rfi ATTORNEYS,

Patented Aug. 4, 1931 UNITED STATES PATENT OFFICE CARL H. BISSELL, OFSYRACUSE, NEW YORK, .ASSIGNOR TO CROUSE-HINDS COMPANY,

01? SYRACUSE, NEW YORK, A CORPORATION OF NEW YORKv AUTOMATIC STOP FORSTART AND STOP MOTORS Ap lication filed April 26,

This invention relates to motors having a start and stop action and hasfor its object, a particularly simple and efficient means for stoppingthe motor to prevent over-run thereof when the coils are deenergized.

The invention consists in the novel features and in the combinations andconstructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanyingdrawings in which like characters designate corresponding parts in allthe views.

Figures 1 and 2 are opposite side elevations, partly in section of aninduction disk motor embodying my invention, Figure 1 being partlybroken away and Figure 2 being fragmentary.

Figure 3 is an elevation looking to the left in Figure 1.

Figure 4 is a fragmentary sectional View showlng the stop arm andoperating means therefor.

This invention comprises a stop to obstruct the rotation of the rotor ofthe motor and an electro magnetically operated member operated by thefield coils or one of them to control the operation of the stop.

I have here shown my invention as embodied in an induction disk motor.

1 designates the disk or rotor.

2 are the filed coils.

3 are the poles.

4 are shading coils usually provided on the pole pieces.

5 is the shaft on which the disk 1 is mounted.

The shaft is supported in any suitable manner on a frame 6 and it isconnected through suitable gearing 7 and 8 to a shaft 9 connected to themechanism actuated by the motor. This may be of any mechanism requiringaccurate timing particularly as to starting and stopping as forinstance, mechanism for controlling street traflic signals, that is,signals where the go signal or green lamp is displayed north and southat a plurality of intersections and the stop or red signals displayed onintersecting streets at the same time, or the green signals on onestreet at one intersection may alternate with 1923. Serial No. 273,019.

the'redsignals on the same street but at the next intersection.

The disk 1 isprovided with one or more stop shoulders 10.

11 designates the stop for coacting with the stop shoulders to stop themotor, this being here shown as an arm pivoted at 12 to a bracket 13secured to the base 14 of the frame as by screws 15, the arm being hereshown as extending substantially tangential to the disk 1. In theillustrated embodiment of my invention, the arm is normally arranged inthe path of the shoulders 10 although in so far as the stoppingoperation is concerned, it may but momentarily move into the path ofsaid shoulders and remain there only long enough to engage one of theshoulders and stop the disk 1.

The electro-magnetic means for operating the stopcomprises an armaturemember 16 arranged within the field of one of the coils 2 or pole 3thereof and in order to be shifted by the electro-magnetic field whenthe field coil is energized. This member 16 is here shown as an armpivoted upon the same pivot 12 that the stop arm 11 is mounted. The arm16 is arranged at an angle to the arm 11 and extends toward the centerof the disk in a general radial direction.

A spring 18 is coiled about the pivot 12 and anchored at one end at 19to" the base 14; and thrusting at its other end against the stop arm 11.The arms 16 and 11 are connected by suitable means as a yoke 20. Theoutward movement of thestop arm is limited by a shoulder 21.

In operation, when a switch is operated to close the circuit through thecoils 2, the disk 1 is actuated and the inductive action of the coils 2or the pole piece 3 thereof moves the arm 16 outwardly, thus moving thestop arm- 11 out of the path of the shoulders 10 where it remains aslong as the circuit is closed through the field coils and at the sametime tensioning the spring 18. When this circuit is opened, the spring18 reacts and returns the stop arm 11 with a snap action to its positionin the path of the shoulders 10 and stops the rotor so that thesynchronism of the mechanism operated by the motor with respect to othersimilar mechanism is not upset by over-running of the motor.

lVhat I claim is:

1. The combination of an induction disk motor having a disk rotor andfield coils and poles, the disk being provided with a peripheral stopshoulder, a pivoted stop arm extending in a. direction tangential to thedisk and movable into the path of said shoulder, a pivoted armaturemember arranged at an angle to the stop arm and normally extendingtoward the center of the disk and in the field of one of the field coilsto be operated thereby to move the stop arm away from the rotor when thefield coils are energized and a spring tending to hold the stop arm andthe armature arm in their normal positions.

2. The combination of an electric motor having a rotor, field coils andpoles, the rotor having projections thereon, a stop member normallyarranged in position to engage the projections on the rotor, an armatureelement arranged in the magnetic field of one of the field coils to beoperated thereby when the field coils are energized, said means beingconnected to the stop member to shift the same out of its normalposition when the field coils are energized to actuate the rotor, andmeans for returning the stop to engage the projections on the rotor whenthe coils are deenergized, thereby simultaneously stopping movement ofthe rotor.

3. The combination of an electric motor having a. rotor, field coils andpoles, the rotor having engaging means thereon, a stop member normallycoacting with the engagement means on the rotor, an armature elementconnected with the stop member and magnetically operated by one of thefield coils to disengage the stop member when said field coil isenergized, and means to return the stop member to engagement with theengaging means on the rotor upon failure of current in the field coil,whereby movement of the rotor is considerably arrested.

4. The combination of an electric motor having a rotor, field coils andpoles, the rotor including a disk having a series of peripheral stopshoulders, a stop member movable into and out of the path of theshoulders, an armature element arranged in the field of one of the coilsto be actuated thereby when the field coils are energized to hold thestop element out of the path of the shoulders and to permit the stopelement to engage the shoulders upon failure of current in the fieldcoils and thereby instantaneously stop rotation of the rotor.

In testimony whereof, I have hereunto signed my name, at Syracuse, inthe county of Onondaga and State of New York, this 6 day of April, 1928.

CARL H. BISSELL.

